Bile duct injury as a major cause of stenosis and occlusion in transjugular intrahepatic portosystemic shunts: Comparative histopathologic analysis in humans and swine

PURPOSE: A comparative histologic analysis of human and swine transjugular intrahepatic portosystemic shunts (TIPS) was performed to investigate factors limiting TIPS patency and to further develop an animal model for TIPS. MATERIALS AND METHODS: Twenty-one human and 13 porcine shunts were evaluated by means of gross inspection, histologic evaluation, and electron microscopy. RESULTS: Severe stenosis (>75% narrowing) or occlusion was detected with portal venography in nine of the 21 human shunts (48%) and in 10 of 13 porcine shunts (77%). Gross or histologic evidence of a substantial biliary fistula was observed in seven of nine porcine shunts and in seven of eight human shunts with severe parenchymal tract stenosis or occlusion. No evidence of substantial bile duct injury was identified in the 13 human shunts or two swine shunts with patent, nonstenotic parenchymal tracts (P < .01, Fisher exact). Histologic findings in porcine shunts mimicked human tissue responses, including a metaplastic proliferation of bile duct epithelium at sites of bile duct transection. CONCLUSION: Bile duct transection and bile leak are significantly associated with TIPS parenchymal tract abnormalities in patients and swine. TIPS in swine created with the Wallstent faithfully reproduce gross morphologic and histologic changes observed in patients.